diff --git a/python/plugins/processing/gui/ListMultiselectWidget.py b/python/plugins/processing/gui/ListMultiselectWidget.py
index 8a53e6450b3..37f7c4e6ebf 100644
--- a/python/plugins/processing/gui/ListMultiselectWidget.py
+++ b/python/plugins/processing/gui/ListMultiselectWidget.py
@@ -150,7 +150,7 @@ class ListMultiSelectWidget(QGroupBox):
 
     def _setupUI(self):
         self.setSizePolicy(
-            QSizePolicy.Preferred, QSizePolicy.Ignored)
+            QSizePolicy.Preferred, QSizePolicy.Preferred)
 
         self.setMinimumHeight(180)